What is a “resource” in Rails?

Question

Dumb question but I have some lingering confusion of what, exactly, a \"resource\" is in Rails. The term is used everywhere but I get a funny feeling it might be being used

Answer 1

Here's a good article discussing how most developers think that "Resource" is synonomous with the database table, the argument, I guess, being that mapping to the resource is mapping the controller to that database table (or, with ActiveResource, to another REST url).

Basically, I think a "resource" is "persisted data." map.resources maps the 7 RESTful actions to a particular suite of persisted data.

But I haven't thought about it too much in depth. Good question!

Answer 2

Any object that you want users to be able to access via URI and perform CRUD (or some subset thereof) operations on can be thought of as a resource. In the Rails sense, it is generally a database table which is represented by a model, and acted on through a controller.

For example, you might have a User resource (with a users table in your DB). This is represented by a User model, is mapped to users_controller with map.resources :users (which then generates routes like /users (a collection of User resources) and /users/1 (a specific User resource).

You act upon those resources by using the appropriate HTTP method when making calls to those resources. POST to the resource collection (/users) creates a new record; GET retrieves a list of resources (/users) or a specific user (/users/1). PUT updates a specific user (/users/1/), and DELETE destroys that user. The URLs are the same, but the result (and controller action) may be different based on the HTTP verb. The idea, though is that /users/1 always means "I'm interacting with the User that has ID #1", regardless of the action.

Answer 3

A lot of people here say that resources refer to the database tables you have. It might be true sometimes but not necessarily true always. I could give you a lot of examples where you don't have a corresponding table in your database for a particular resource. Hence asssociating it with tables is rather wrong.

I would define a resource as a route which maps to related requests. So instead of declaring separate routes for the actions you want to do you can simply declare them using a resourceful route.In Rails, a resourceful route provides a mapping between HTTP requests and URLs to controller actions.

So say you define resources :users in config/routes.rb.
You can now use a number of helpers to the controllers in your application like edit_user_path which returns users/edit .

Answer 4

I think they probably mean it in the general web sense, i.e., Resource (Web):

the referent of any Uniform Resource Identifier

I don't think it has anything to do with database tables.

Answer 5

open your model folder, that is a hint of what resources you have! example: users, pictures, comments...

Answer 6

Here's a good link: https://api.rubyonrails.org/v5.2.1/classes/ActionDispatch/Routing/Mapper/Resources.html

Which basically says: Resource routing allows you to quickly declare all of the common routes for a given resourceful controller. Instead of declaring separate routes for your index, show, new, edit, create, update and destroy actions, a resourceful route declares them in a single line of code:

resources :photos